Understanding Coorong nutrient dynamics
The Southern Coorong is currently in a high nutrient state due to reduced flushing of salt and nutrients from the system, which has impacted on the quality of water and sediment habitats for macroinvertebrates, plants, fish and waterbirds.
What we are doing
Knowledge of nutrient cycling processes in the Coorong South Lagoon is critical to the development of short and long-term management actions that will improve water quality and support habitat requirements for plants, waterbirds and fish.
Research is currently being undertaken to improve knowledge of the drivers and sources of undesirable nutrients, which are causing poor water and sediment quality in the Coorong. This involves undertaking sampling to assess the nutrients in the water and the interaction with other drivers of poor water quality to determine how to manage nutrient levels to improve water quality.
Studies are underway to consider nutrient removal options at a system scale. Key findings and strategies are being considered and will provide the basis for potential future management activities.
What we have done so far
Key developments and findings from investigations include:
- The Trials and Investigations team has been surveying sediment and water quality as well as collating and reviewing existing data.
- The Coorong South Lagoon is hypersaline (high salinity) and hypereutrophic (high in nutrients) and reduced flushing has resulted in prolonged periods of this state.
- Poor sediment quality (sulphide rich sediments) is widespread with few benthic (living on the bottom) organisms present. These factors are negatively impacting on benthic flora and fauna communities
- Coorong water quality synthesis with a focus on the drivers of eutrophication
- Sources and transport of nutrients in the Coorong
- Coorong nutrient cycling and fluxes
- A scientific evaluation to inform nutrient removal options for the Coorong
- Nutrient cycling in the Southern Coorong
- The role of sediments in the eutrophication of the Southern Coorong
- Monosulfidic black oozes are anoxic and alter nutrient cycles
- Pathways to reversing the hypereutrophic nutrient state of the Coorong